Index: openacs-4/packages/acs-bootstrap-installer/tcl/20-db-bootstrap-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/acs-bootstrap-installer/tcl/20-db-bootstrap-procs.tcl,v
diff -u -N -r1.9.2.4 -r1.9.2.5
--- openacs-4/packages/acs-bootstrap-installer/tcl/20-db-bootstrap-procs.tcl	4 Feb 2017 14:08:13 -0000	1.9.2.4
+++ openacs-4/packages/acs-bootstrap-installer/tcl/20-db-bootstrap-procs.tcl	21 May 2017 09:19:36 -0000	1.9.2.5
@@ -232,14 +232,19 @@
             ns_db releasehandle $db
             if { $this_suffix eq "" } {
                 ns_log Notice "$proc_name: couldn't determine RDBMS type of database pool \"$pool\"."
-                lappend bad_pools "<li>OpenACS could not determine the RDBMS type associated with
-    pool \"$pool\"."
+                lappend bad_pools "<li>OpenACS could not determine the RDBMS type associated with pool \"$pool\"."
                 set long_error 1
             } elseif { [nsv_get ad_database_type .] eq "" } {
                 nsv_set ad_database_type . $this_suffix
+                #
+                # For the time being, keep the info in the nsv for
+                # backwards compatibility and and a version in a
+                # per-thead (namespaced) variable
+                #
+                set ::acs::database_type $this_suffix
+                
             } elseif { ![string match $this_suffix [nsv_get ad_database_type .]] } {
-                ns_log Notice "$proc_name: Database pool \"$pool\" type \"$this_suffix\" differs from
-    \"[nsv_get ad_database_type .]\"."
+                ns_log Notice "$proc_name: Database pool \"$pool\" type \"$this_suffix\" differs from \"[nsv_get ad_database_type .]\"."
                 lappend bad_pools "<li>Database pool \"$pool\" is of type \"$this_suffix\".  The
     first database pool available to OpenACS was of type \"[nsv_get ad_database_type .]\".  All database
     pools must be configured to use the same RDMBS engine, user and database."
Index: openacs-4/packages/acs-tcl/tcl/00-database-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/acs-tcl/tcl/00-database-procs.tcl,v
diff -u -N -r1.88.2.17 -r1.88.2.18
--- openacs-4/packages/acs-tcl/tcl/00-database-procs.tcl	22 Apr 2017 18:11:54 -0000	1.88.2.17
+++ openacs-4/packages/acs-tcl/tcl/00-database-procs.tcl	21 May 2017 09:19:36 -0000	1.88.2.18
@@ -236,12 +236,24 @@
 
 
 ad_proc -public db_type {} {
-    @return the RDBMS type (i.e. oracle, postgresql) this OpenACS installation is using.  The nsv ad_database_type is set up during the bootstrap process.
+    @return the RDBMS type (i.e. oracle, postgresql) this OpenACS installation is using.
+    The nsv ad_database_type is set up during the bootstrap process.
 } {
+    #
     # Currently this should always be either "oracle" or "postgresql":
     # --atp@piskorski.com, 2003/03/16 22:01 EST
-
-    return [nsv_get ad_database_type .]
+    #
+    # First check, if the database type exists in the namespaced
+    # variable. This should be always the case. If this fail, fall
+    # back to the old-style nsv (which can be costly in tight db loops)
+    #
+    if {[info exists ::acs::database_type]} {
+        set result $::acs::database_type
+    } else {
+        set result [nsv_get ad_database_type .]
+        ns_log Warning "db_type '$result' had to be obtained from the nsv 'ad_database_type'"
+    }
+    return $result
 }
 
 ad_proc -public db_compatible_rdbms_p { db_type } {